1. Technical Field of the Invention
The present invention concerns a noncontact ID (identification information) card or the like and a manufacturing method of the same.
2. Related Art
Conventionally, the classification information is obtained by many types of bar codes printed or adhered on a card type paper, for instance, such as a tag attached to a merchandise and such bar codes, being simple printing to the paper, presents a high productivity and a low cost.
On the other hand, the IC (integrated circuit) chip, different from the bar code, not only indicates information, but also increases the quantity of information by leaps and bounds and, at the same time, permits to rewrite the information. Moreover, the IC chip is being increased in the productivity and reduced in the price. Therefore, a so-called noncontact ID card, noncontact tag or the like packaging IC chips on an antenna circuit board (such things shall be called collectively noncontact ID card or the like, hereinafter.) comes to be used.
As it is well known, the noncontact ID card or the like hides a broad applicability for ID recognition, electronic settlement, or others, because they can read and write simultaneously a quantity of information and, what is more, assure a high security. Consequently, their wider use can be accelerated by leaps and bounds, provided that their manufacturing cost is reduced.
However, the noncontact ID card or the like are manufactured, in general, by heat pressing antenna electrodes 3a, 3b of an antenna circuit board 2 to which an anisotropic conductive film (ACF) 1 and bumps 5a, 5b of the IC chip 4 in a precisely registered state, in short, by bonding the both, as shown in FIG. 16.
As a result, a high accuracy bonder installation is required, and there was a problem of high manufacturing cost (mainly packaging cost). What is more, it is extremely difficult to prevent the increase of manufacturing cost, because the productivity lowers though the bonding installation price tends to rise a degree as a more accurate packaging technology is required, according to a further size reduction and miniaturization of the IC chip 4.
It should be appreciated that the bumps 5a, 5b of the IC chip 4 are bonded by heat pressing to the antenna electrodes 3a, 3b of the antenna circuit board 2 in a manner to straddle an antenna 6 connected to them; however, the antenna 6 is formed into a plurality of turns as, for instance, 6 turns or others (refer to FIG. 17), and defines the antenna electrodes 3a, 3b at both ends thereof. Consequently, the line width of the antenna 6 should be miniaturized following the size reduction and miniaturization of the IC chip 4, and a high precision antenna forming technology is required; so it was difficult to prevent the increase of manufacturing cost, also from this point.
It is a first object of the present invention to provide a noncontact ID card or the like allowing to project the prevention of increase of manufacturing cost (mainly packaging cost) of noncontact ID card or the like, by permitting to register easily the electrode of the chip and the antenna electrode of the antenna circuit board, even if the IC chip is reduced in size and miniaturized, and a manufacturing method of the same.
Also, it is a second object thereof to provide a noncontact ID card or the like allowing to keep the electric bonding state of the electrode of the IC chip and the antenna electrode of the antenna circuit board satisfactory (keep in the conductive state) in addition to the insulation of the predetermined points, even for the noncontact ID card or the like of the laminated structure of the antenna circuit board and interposer board and a manufacturing method of the same.
In order to achieve the aforementioned objects, the noncontact ID card or the like of the present invention comprises an antenna circuit board with an antenna formed on a substrate, and an interposer board with an expanded electrode formed on a substrate where an IC chip is embedded, the expanded electrode being connected to an electrode of the IC chip, wherein both boards are laminated in a manner to bond the electrode of the antenna and the expanded electrode.
As both boards are laminated in a manner to bond the electrode of the IC chip and the antenna electrode through the expanded electrode in this way, both electrodes can be registered easily each other despite the IC chip size reduction and miniaturization and, consequently, the increase of manufacturing cost (mainly packaging cost) of noncontact ID card or the like can be prevented.
In the present invention, for bonding the antenna electrode and the expanded electrode, the antenna electrode and the expanded electrode may be bonded by an electric conductive adhesive agent, or the antenna electrode and the expanded electrode may be bonded directly, by gluing the substrate of the antenna circuit board and the substrate of the interposer board.
Also, an insulating adhesive agent is preferably disposed between the substrate of the antenna circuit board and the substrate of the interposer board, in a way to seal an antenna formation portion of the antenna circuit board and an electrode formation portion of the IC chip. Further, the IC chip electrode may have advantageously an under barrier metal layer.
The insulation of predetermined points and the bonding of both boards can be reinforced by charging insulating adhesive agent between the antenna circuit board and the interposer board, and the electric bonding state of the electrode of the IC chip and the antenna electrode of the antenna circuit board can be kept satisfactory (kept in the conductive state), by forming the under barrier metal layer (UBM layer) on the IC chip electrode. It should be appreciated that the substrate of the interposer board and the substrate of the antenna circuit board may be composed of a resin film.
On the other hand, the manufacturing method of the noncontact ID card or the like of the present invention comprises steps of electrode formation for forming an expanded electrode on a substrate of an interposer board where an IC chip is embedded, the expanded electrode being connected to an electrode of the IC chip, and board lamination for laminating the interposer board and an antenna circuit board in a way to bond an antenna electrode formed on a substrate of the antenna circuit board and the expanded electrode.
Thus, as the expanded electrode is formed on the substrate of the interposer board where the IC chip is embedded, and both boards are laminated in a manner to bond the expanded electrode and the antenna electrode, both electrodes can be registered easily each other despite the IC chip size reduction and miniaturization and, consequently, the increase of manufacturing cost (mainly packaging cost) of noncontact ID card or the like can be prevented.
In case of interposing insulating adhesive agent between both substrates, both boards may be laminated after an adhesive agent application step for applying insulating adhesive agent to the interposer board, which have been through the electrode formation step, in a way to coat an electrode formation portion of the IC chip. Besides, the expanded electrode can be formed easily by the screen printing method.